MERRA-2 Land Ice Surface Diagnostics at 3-Hourly Resolution

MERRA-2 tavg3_2d_glc_Nx is a 3-hourly time-averaged data collection providing assimilated land ice surface diagnostics. The dataset is produced by NASA's Global Modeling and Assimilation Office using the GEOS model and covers the period from 1980 to the present. It includes variables such as fractional area of glaciated surface snow cover, snow mass, and snow depth.

Use Cases

• Model snow mass over glaciated surface using 3-hourly assimilation data to improve hydrological forecasts.
• Analyze trends in fractional area of glaciated surface snow cover from 1980 to present for climate change impact studies.
• Validate satellite snow depth products against the assimilated snow depth over glaciated surface field.
• Study the total snow mass residual due to densification to understand snowpack compaction processes.

Strengths

• Provides global coverage at a 0.625 x 0.5 degree spatial resolution.
• Offers a long temporal record spanning from 1980 to present.
• Data is available at a high 3-hourly temporal frequency (e.g., 01:30, 04:30 UTC).

Limitations

• Data has an approximate latency of 3 weeks after the end of a month, limiting real-time analysis.
• As a reanalysis product, accuracy is dependent on the underlying model and assimilation system.
• Specific row counts and file sizes are not provided in the description.

Provenance

Source

NASA Global Modeling and Assimilation Office (GMAO) via the GES DISC.

Collection Method

Assimilated data product generated using the Goddard Earth Observing System Model (GEOS) version 5.12.4.

Time Range

1980 to present.

Freshness

Updated monthly with a ~3-week latency.

Geography

Global.